The pursuit of science is an interesting endeavor and I’m convinced most folks don’t understand how it actually works. It’s a simplification of the process, but science proceeds in three steps. First, observe the natural world and notice some process or event that may possibly be explained by some other process or event. Second, hypothesize the relationship between the causative event and the resultant action. This is sometimes referred to as a theory. Third, extensively test the theory of events until it is shown to be false. Theories, which are not definitively false may, or may not, be true. The longer they survive testing without being shown to be false, the more likely they are to be true.
Some theories can be proven to be true mathematically and become laws of nature. Gravity is one example. Others are not easily mathematically modeled and remain theories even though they have survived repeated testing and are accepted by most as generally true. Evolution is in this category.
Over two decades ago, some environmental scientists noticed long term, worldwide temperatures appeared to be rising and seemed to correlate with increases in atmospheric carbon dioxide (CO2).